Insulated gate bipolar transistors (IGBTs) are widely used as power devices because they could have breakdown voltages that are equal to or higher than 600 V. IGBTs are designed such that when a voltage is applied in a forward direction the current at a steady state is not saturated, which prevents “latch-up” in the device. However, when a conducting IGBT is switched to a non-conducting state (“turned-off”), current may concentrate and latch-up may occur causing device breaking down. Particularly, in order to reduce the size of a chip, it is necessary to increase current density while avoiding a breakdown during turn-off operations.